Dynamic-strain-based damage evaluation of field-welded beam-to-column connections in steel frames
Commercialized monitoring systems for seismic damage evaluation of steel frames often use maximum response values to infer performance with respect to design limits.These approaches are partly affected by a familiarity of structural engineers to engineering design parameters,an insensitivity of vibration characteristics to local damage as well as an uncertainty on the influence of non-structural and/or secondary component damages.Dense arrays of high-sensitivity strain sensors offer an ability to evaluate localized structural damage,e.g.,beam-end fractures in steel frames,accurately and with robustness to complex phenomena such as damage interaction.This paper presents a dynamic strain-based damage evaluation method and its further development for damage assessment of field-welded beam-to-column connections in steel frames.Field-welded beam-to-column connections are usually composed of web-bolted and flange-welded parts; the bolted connection typically loses resistance after web yielding.It is necessary to quantify the effect of bolt slippage on the damage index in order to accurately determine the damage state of the connection.In this paper,the bolt slippage effect is studied through a closed-form equation and a series of quasistatic tests on a beam-column assembly.The equation is formulated using an equivalent beam model that considers an influential area of each bolt.Then,the technique is applied to measurements of an 18-story steel frame test at the E-Defense shaking table facility,with the goal of evaluating local damage at field-welded beam-column connections.Damage quantification results are compared with the observed damage at several input ground motion levels and the accuracy of the proposed method is discussed.
Steel frames Field-welded beam-to-column connection Dynamic strain response Damage evaluation
M.Kurata X.Li T.Matarazzo
Disaster Prevention Research Institute,Kyoto University,Uji,Japan School of Civil Engineering,Chongqing University,Chongqing,China Senseable City Laboratory,Massachusetts Institute of Technology,Cambridge,MA USA
国际会议
The 7th World Conference on Structural Control and Monitoring(7WCSCM)(第七届结构控制与监测世界大会)
青岛
英文
2680-2691
2018-07-22（万方平台首次上网日期，不代表论文的发表时间）